Casing-perforator.



L. E. STEPHENS. GASING PERFOBATOB. APPLIOATION FILED JUNE 18, 1907.

Patented Nov.24, 1908.

gulmww I UNrriaD STATE-s PATENT orricn.

LEWS E. STEPHENS, O13?"I FULLERTON', CATIFORNIA.

onsmr'nnronuon.

Specification of Letters Patent.

i Patented Nov. 24, 1908*.

Application mea rune 1s, 1907. serial No. 379,566.

To all whom it may concern:

Beit known that I, LEWIS E. STEPHENS, a

s citizen of. the United States, residing at Fullerton, in the county of Orange4 and State of'hCalifornia, have invented new and useful Improvements in Casing Perforators, of whichthe following is a specification.

The object of my invention is to provide' a perforator which. may be operated to perforate casing by the weight of the tools above the perforator and which, when such perforations are completed', may be hoisted out of the casing wit-hout being liable to catch therein.

A further object is to provide a perforator which isf simple in construction and which may be easily taken apart for repairs. y -I accomplish these objects by means of the. device described herein and illustrated the accompanying drawings, in which Figure 1.--is an elevation of my complete casing perforator. Fig. 2;-is a longitudinal section ofthe same taken on line 2 2 of Fig. 4. Fig. 3.-i's a longitudinal section taken on line 3-,3 of Fig.v 4. Fig. 4.-lis-a cross section taken on line 4-4 of Fi 1. Fig. 5.-'-is a cross section taken on nes .5 5 of4 Figs. 2 and 3.. Fig. 6.-is a rear mandrel provided with a central longitudielevation of one of the slips showing the groove therein for the reception lof the retaining pin. v

Referring to the drawings 10- designates a into'in'clined grooves 18 on either side 0f extension 19 of stem 12. Upon the vdownwardmovement of stem-12'1n mandrel 10 holders 14 are forced outwardly and punches 15 are forced into engagement vwith andthrough the lcasin in'which the mandrel is adapted to loose y it. Hardened bearing plates 20 are 'provided for holders 14 in the lower end of guideway 13 being held therein by screws.21 so as to be removable' in case of wear.

Mounted in. inclined dovetailed guideways 25 at the upper end of mandrel 10l are two slips 26 provided on their outer cylindrical faces with teeth 27 adapted toengage with the insidey of the casing and prevent thev mandrel from moving downwardly therein.

- Coiled springs 28 "mounted in recesses 29 directly under slips 26 are adapted toforce the slips upwardly and outwardly along inclined guideways 25, the slips 26 beingl normally held against anyf upward movement by eccentric pins 30 on the outer ends of a transverse shaft 31 mounted in bore 32 in the mandrel. Pins 30 engage with slots.33 in the rear faces of slips 26, the pin beingnormally in the position shown in dotted lines in Fig. 6, being in engagement with the upper right angled portion 34 ofv slot 33-, and thereby preventing the upward movenient of slips 26. Upon the rotation of shaft 31 in the direction shown by the arrow in Fig. 6 pin 30 is movedout of engagement with the upper right angled end 34 of slot 33l and moved directly over slot 33 thereby permitting slips 26 .to be forced upward-ly by springs 28. The rotation of shaft 31 is accomplished by the engagement of. dog 35,v

rigidly mounted on the shaft, with the cas. ing on the upward movement of the perforator. Dog 35 is provided with teeth on its` outer end adapted to engage the inside of the casing and stands normally in a position shown in the drawings so that anyupward movement of the perforator will throw dog v35 downwardly.

Stem 12 is provided on its upper end; with a sub 40 adapted. to connect througlr taper joint 41' with a string of drilling tools, a

lock nut 42 is on stem 12 preventing thel dis.

engagement of sub 40'. To. tale the perfo ratorapart it is only necessary to remove the Sub from the upper end of the stem whenv the stem may be sllpped-- downwardlyout of the mandrel. To provide for the renewal of punches 15 without the necessity ofremov- 1 ng the stem slots 43 are cut intothemandrel opposite; screws I6' so that they maybe removed and new punches inserted.

The operation of my erforator is as fol- -lows The perforator 1s rst lowered into the casing to the lowermost point at which the perforations'are wished to be'ma-de and then moved upwardly a slight distance to free slips 26 by the operation of dog 35. Slips 26 are thenforced outwardly by their sprlngs into contact with the casing and is then hoisted through the distance desired v between adjacent perforations and the operation is repeated. When the perforations have been completed the perforator may be hoisted out of the casing without any interference by the slips as the are constructed so as to only prevent the ownward motion of the perforator.

'Having described my invention what I claim as new and desire to secure by Letters Patent is 1. In a casing perforator a hollow mandrel, a plurality of casing uiiches mounted in said mandrel so as to side transversely therein, a movable stemA mounted in said mandrel, said stem being provided with inclined guideways adapted to engage and re- 1 cifprocate said punches upon the movement the stern, and means to hold the mandrel against ldownward movement in the casing.

2. In a casing perforator 'a hollow mandrel provided, with transverse guideways therein, casing punches adapted to reciprocate in said guideways, a vertically movable stem moiited in said mandrel-and adapted to be connected at -its upper end. with a of drilling tools, said stem being prostrincgl 4vide with inclined guideways on its lower end adapted to engage with corresponding guideways on said casing unches arid to move said punches outward y on the downward movement of the stem, a plurality of slips mounted in inclined guideways in said mandrel and adapted to Contact with the casing and revent the downward movementof the per orator, and means to hold said slips out of engagement with the casing.

3. In a'casing erforator, ahollow man! drelprovided with transverse guideways,-

casing punches adapted to reciprocate in said guideways, a vertically movable stem )mounted in said mandrel and adapted to b'e reciprocated by a string of .drilling tools, said stem being prvided with inclined guideways on its lower Aend adapted to engage with corresponding guideways on said punches and to move said punches outwardly on the. downward movement of the stem in the mandrel, and means lto hold the mandrel against downward movement in the casing.

4. In a casing perforator, a hollow mandrel, a plurality of casing punches mounted drel, a movable stem mounted in said mand'rel, casing punches mounted in said mandrel and adapted to be operated by the movements of said stem, means mounted on said mandrell to engage with the casing, meansto` lock said engaging means in its inoperative position, and means to release said locking means.

6. A casing perforator comprising a mandrel, a vertically movable stemikmounted in said mandrel, casing punches mounted in said mandrel and adapted to be forced outwardly by the downward movement of the stem, gripping means mounted on said man,- drel and adapted to yengage with the casing to prevent the downward movement of said mandrel, means to lock said gripping means out of engagement with tne casing, and means engaging with the casing to unlock said gripping means .upon an upward movement of said mandrel in the casing.

7. A casing perforator comprising a mandrel, a vertically movable stem -mounted in said mandrel, casing punches mounted in;

lower inoperative position, and an operating arm attached to said cam, said arm projectingout of said mandrel and adapted to contact with the casing.

In witness that I` claim the foregoing I haver hereunto subscribed my name this 8th day of June, 1907. i

LEWIS E. STEPHENS.

Witnesses:

TRIMBLE BARKELEW, EDMUND A. STRAUSE. 

